In switchgear cabinets or subrack carrier housings known from the state of the art, the internal components need to be cooled with air currents. In order to simultaneously prevent soiling of the respective interior, the air is usually cleaned by means of a filter element before it is admitted into the housing.
The insertion and removal of the filter elements has proved quite problematic in practical applications. The filter elements need to be exchangeable and cover a ventilation opening in the switchgear cabinet at a location that is difficult to access. When changing the filter element, it also needs to be taken into account that cables, optical waveguides or other components in the switchgear cabinet or in its immediate vicinity cannot form an obstruction or be damaged. In addition, cable ducts frequently extend to the actual switchgear cabinet underneath or laterally thereof such that the insertion of the filter elements, in particular, into the preferred bottom region of the housing is quite complicated and associated with the risk of damaging the switchgear cabinet components.
DE 198 17 387 B2 discloses an air-conditioning system for a switchgear cabinet, in which the filter element is arranged in an air duct such that it is inclined relative to the vertical by a certain angle, wherein the filter element is fixed in position by means of a spring element. The disadvantage of this embodiment can be seen in that the arrangement of a filter element requires much space. The exchange of the filter element is also still a relatively complicated procedure and only possible if direct access to the ventilation channel is provided.
DE 7500977 discloses an air filter housing with a tensioning device that serves for accommodating filter cells for cleaning air or gases. In this case, the filter elements can be pressed against contact surfaces with the aid of a spindle. However, the arrangement and the exchange of the filter elements are still quite complicated.
CH 448 693 discloses a pressing device for tightly inserting exchangeable filters into exhaust air ducts. The filter elements are moved into their pressing position and disengaged therefrom by means of a toggle lever mechanism. This variation has a complicated constructive design and requires much structural space (particularly for the actuation).
Consequently, the invention is based on the objective of developing a filter system, particularly for switchgear cabinets or subrack carriers, in which the filter element(s) can be easily exchanged without affecting or damaging external or internal components of the switchgear cabinet or subrack carrier and without noteworthy modifications to the switchgear cabinet design.